Joomla 3.8.9 und 3.8.10
This Joomla Update was released at the same day like Joomla 3.8.9 and fixes a problem with windows servers caused by Joomla 3.8.9.
Joomla 3.8.9 fixed a security issue related to installations using PHP 5.3 (hopefully not concerning you, because you already switched to newer PHP versions a long time ago) and an XSS vulberability related to the language switcher module.
Joomla 3.8.9 braught more than 50 small improvements and bugfixes. A detailed listing of the improvements you find on https://github.com/joomla/joomla-cms/milestone/35?closed=1
Die Joomla Updates 3.8.9 and 3.8.10 were released on June 26, 2018